Roast Chicken with Potatoes and Leeks | The Fancy Pants Kitchen

Ingredients

• 3 tbsp whole-grain mustard
• 3 tbsp extra-virgin olive oil
• 1 tbsp apple cider vinegar
• 2 tsp brown sugar
• 6 cloves garlic, 2 cloves minced and 4 cloves thinly sliced
• 1 (4-to 5-pound) whole chicken
• 1 tbsp plus 1 teaspoon kosher salt
• 1/4 tsp freshly cracked black pepper, plus more for serving
• 3 large leeks, trimmed and thinly sliced (about 3 cups)
• 2 lemons, thinly sliced
• 1 cup white wine
• 1 pound smallish new potatoes or petite gold
• 1 tbsp chopped fresh tarragon, plus more for serving
• 4 tbsp salted butter, cold